ComponentFactory.Krypton.Toolkit.RenderGlassHelpers.DrawBackGlassBottom C# (CSharp) Method

        public static IDisposable DrawBackGlassBottom(RenderContext context,
                                                      Rectangle rect,
                                                      Color backColor1,
                                                      Color backColor2,
                                                      VisualOrientation orientation,
                                                      GraphicsPath path,
                                                      IDisposable memento)
        {
            using (Clipping clip = new Clipping(context.Graphics, path))
            {
                MementoDouble cache;

                if ((memento == null) || !(memento is MementoDouble))
                {
                    if (memento != null)
                        memento.Dispose();

                    cache = new MementoDouble();
                    memento = cache;
                }
                else
                    cache = (MementoDouble)memento;

                // Draw the one pixel border around the area
                cache.first = DrawBackLinear(rect, false,
                                             ControlPaint.Light(backColor1),
                                             ControlPaint.LightLight(backColor1),
                                             orientation, context.Graphics,
                                             cache.first);

                // Reduce size on all but the upper edge
                ModifyRectByEdges(ref rect, 1, 0, 1, 1, orientation);

                // Draw the inside areas as a glass effect
                cache.second = DrawBackGlassRadial(rect, backColor1, backColor2,
                                                   _glassColorTopD, _glassColorBottomD,
                                                   3f, 1.1f, orientation, context.Graphics,
                                                   _fullGlassLength, cache.second);
            }

            return memento;
        }